Electrical switch-board



(No Model.)

J. B. ODELL.

ELECTRICAL SWITCH BOARD.

No. 252,395. Patented Jan.17,1882.

UNITED STATES PATENT OFFICE.

JOHN B. ODELL, OF CHICAGO, ILLINOIS.

ELECTRICAL SWITCH-BOARD.

, SPECIFICATION forming part of Ltters Patent No. 252,395, dated January 17, 1.8 82.

' Application tiled Jul 20, 185i. (X0 model.) I

To all whom 'tt may concern Be it known that I, JOHN B. ODELL, of Chicago, Cook county, Illinois, have invented certain new and useful Improvementsin Switch- Boards, of which the following is a specification.

My invention relates to improvements in that class of switch-boards for-telegraph-lines in which the wires to be conncctedare attached to metallic strips arranged at right angles to each other. Such boards are usually secured to the wall in a vertical position, and diiticulty heretofore has been experienced in keeping the switchplug in place to properly form the connection between the strips, especially where the telegraph-stationis situated near a railroad-track, as the jarring caused by the passage of trains tends to loosen and disengage the locking. devices which heretofore have been employed to keep the plug in place.

The object ofthe present invention is to provide a cheap, simple, and eflicient means of keep'iug the plug in place, which will not interfere with ease and facility in applying and removing it to and from the board; and to this end myinvcntion consists in providing the strips with countersunk threaded holes for the insertion ot'the plug,the ho'lesintheouter strips being larger than those in the inner strips,

and providing the plug with shoulders and screw-threads adapted to'fitin said holes, the shoulders on the plug being the same distance apart as the strips, so that the plugs will all fit alike, and, being screwed into both strips, tend to holdtlie samerigi'd, and prevent vibration or rattling.

In practical find that it the-threads be cut to tighten the plug W a three quarters turn thereof, it will be su-fiicient to retain the same in place with certainty. It is to he observed that though the. thread at the end of the plug is on a smaller screw, it should be cnta't about the same pitch as the other thread, so-asto bring both shoulders to bearagain t the strips at the same time.

In the accompanying drawings, which form a part of this specification, Figure 1 is a perspective view of adevice embodying my invention, and Fig. 2 is a section on line am: of Fig. 1. p In the drawings similar letters of reference indicate like parts.

A represents the frame or cross-pieces of the switchboard, to which the outer metallic strips, B, are secured by screws or otherwise on one side, and the inner strips, 0, on the other side. the latter being arranged at right angles to the former.

D D are the binding-posts, by which the wires are connected with the strips. The strips 13 are provided with threaded holes I) and the strips 0 with smaller threaded holes 0, the one immediately opposite. the other. The holes are preferably countersunk ormade flaring, as shown at band c, to facilitate the entrance of the plug H. The plug His provided with shoulders h h and screw-threads h h, adapted to lit in the corresponding holes in the strips .15 and G. Y

H isthe handle of the plug, preferably made of vulcanite or otherinsula'ting material. The tip end of the plug is made enough smaller than the other end to pass readily through the threaded holes in the outer strip, B.

Switch-boards may be constructed in this way with any number of strips and cross-strips.

'It is obvious that the strips B and C may, if preferred, be arranged parallel to each other; but I coiisider the arrangement shown the best.

I am aware that switch-boards have heretofore been made having plugs secured to one of the bars thereof by a bayonet'ca-tch, as shown in the patent to O. S. Jones, hie. 90,270, dated May 18, 1869, and also having plugs secured to one of thecross-bars b -'screw-threads,asshown in the patent toE.T. Quimby, No.244,143, dated July 12,'l881, and I hereby disclaim such constructions.

I claim-- In a switch-board, the combination ofstrips -.B, provided with threaded holes I), and crossstrips 0, provided with smaller threaded holes 0, and plug 'H, provided with screw-threads h and It, adapted. .fit in the corresponding holes in said strips and cross-strips, substantially as specified.

JOHN B. ODELL.

Witnesses: 1

T. EVERETT BROWN, H. M, MUNDAY. 

